99xtremedime Posted March 12, 2013 Report Share Posted March 12, 2013 Helping a friend get a box together for his silverado and its not exactly something i can type into torres. The box after sub displacement is 1.01 cubic feet and im looking at using a 4" areo port at 29" long for roughly a 33hz tuning and i know that the port @ 4" diameter, 29" long is 364.24 sq in of port. But i need the port to be be 5" external and the rest inside the box. Does that effect anything? And how would i calculate the port area per foot? -2 AQ HDC3 15's-'Nendo 3KWP @ .5-7.75cuft @ 30hz-Alpine CDA-117-4 Cadence PA 8's -AQ 200.2-2 AQ Supertweeters-XS Power D3400-270a Mecman Alt -Knu Konceptz Wire Link to comment Share on other sites More sharing options...
Nivram Posted March 12, 2013 Report Share Posted March 12, 2013 364.24sq in is alot of port area for a 4in areo port Walled 2002 buick century A.K.A "Betty sue" polk 5 1/2 front doors 4 3in pillar speakers DD 3518's AQ 3500 v2 90ft of 0/1 ga tuned to 40hz :build: http://www.stevemeadedesigns.com/board/topic/162721-buick-built-in-trunk-fi-sp4-hifonics-2400/ Link to comment Share on other sites More sharing options...
Nivram Posted March 12, 2013 Report Share Posted March 12, 2013 smaller the areo port diameter, the lower itl sound with less port length bigger the areo port diameter the longer you will have to make it for the same low tune. Walled 2002 buick century A.K.A "Betty sue" polk 5 1/2 front doors 4 3in pillar speakers DD 3518's AQ 3500 v2 90ft of 0/1 ga tuned to 40hz :build: http://www.stevemeadedesigns.com/board/topic/162721-buick-built-in-trunk-fi-sp4-hifonics-2400/ Link to comment Share on other sites More sharing options...
SGT_76 Posted March 12, 2013 Report Share Posted March 12, 2013 I may be wrong but I thought to calculate port area of an aero port, you just find the area of the opening...4" aero = 12.56" port area? Using this number for your "port area per foot"? But like I said I could be wrong. Link to comment Share on other sites More sharing options...
Nivram Posted March 12, 2013 Report Share Posted March 12, 2013 ^correct Walled 2002 buick century A.K.A "Betty sue" polk 5 1/2 front doors 4 3in pillar speakers DD 3518's AQ 3500 v2 90ft of 0/1 ga tuned to 40hz :build: http://www.stevemeadedesigns.com/board/topic/162721-buick-built-in-trunk-fi-sp4-hifonics-2400/ Link to comment Share on other sites More sharing options...
Nivram Posted March 12, 2013 Report Share Posted March 12, 2013 360 sqin of port would mean you have 30in tall 12in wide wayyy to large for a 1 cube box Walled 2002 buick century A.K.A "Betty sue" polk 5 1/2 front doors 4 3in pillar speakers DD 3518's AQ 3500 v2 90ft of 0/1 ga tuned to 40hz :build: http://www.stevemeadedesigns.com/board/topic/162721-buick-built-in-trunk-fi-sp4-hifonics-2400/ Link to comment Share on other sites More sharing options...
mikeg321 Posted March 12, 2013 Report Share Posted March 12, 2013 First off, a 4" aero has an area of 12.56 sq. in. Your port volume is 364.42 cu. in. Now calculate your box volume in cubic inches. 1 cu. ft.=1728 cu. in. Assuming your doing a single baffle we subtract 5.75" from your port length (its gonna be outside the box so it won't effect the box volume). Now we adjust your port volume 12.56x23.25=292.16 cu. in. Now subtract port volume from box volume 1728-292.16=1435.84 So your box after port displacement is 1435.84 cu. in. Now we have to turn that number to cu. ft to calculate port area per cu. ft. 1435.84÷1728=.83 cu. ft. Finally divide port area by cu. ft. 12.56÷.83=15.13 So you have 15.13 sq. in. Of port per cu. ft. 4 fully loaded Fi sp4 15's 2 Crescendo bc5500s Crescendo c1100.4 6 focal mids Vifa tweets 5 XS Power d3100's Pioneer avh-p4200dvd All crammed into a mustang. http://www.stevemeadedesigns.com/board/topic/150569-mikeg321s-fi-nendo-mustang-getting-walled-videos-page-4/ Link to comment Share on other sites More sharing options...
Nivram Posted March 13, 2013 Report Share Posted March 13, 2013 you will be fine with an external port if you need the extra length for the tune to be right. Walled 2002 buick century A.K.A "Betty sue" polk 5 1/2 front doors 4 3in pillar speakers DD 3518's AQ 3500 v2 90ft of 0/1 ga tuned to 40hz :build: http://www.stevemeadedesigns.com/board/topic/162721-buick-built-in-trunk-fi-sp4-hifonics-2400/ Link to comment Share on other sites More sharing options...
99xtremedime Posted March 13, 2013 Author Report Share Posted March 13, 2013 Thanks for the help man!! So with that setup do you think that it would do pretty good with a sundown sa-10 on roughly 1000-1100 WRMS of power? And one of the things that I was most worried about was having the port be partially external will it effect the tuning at all? Say I run into clearance issues with the magnet and have to move it 2" or so. Would the tuning still be 33hz? I mean, I know that it would change slightly because the internal volume would increase slightly but were only talking a fraction right? First off, a 4" aero has an area of 12.56 sq. in.Your port volume is 364.42 cu. in.Now calculate your box volume in cubic inches. 1 cu. ft.=1728 cu. in.Assuming your doing a single baffle we subtract 5.75" from your port length (its gonna be outside the box so it won't effect the box volume). Now we adjust your port volume 12.56x23.25=292.16 cu. in.Now subtract port volume from box volume 1728-292.16=1435.84So your box after port displacement is 1435.84 cu. in.Now we have to turn that number to cu. ft to calculate port area per cu. ft. 1435.84÷1728=.83 cu. ft.Finally divide port area by cu. ft. 12.56÷.83=15.13So you have 15.13 sq. in. Of port per cu. ft. -2 AQ HDC3 15's-'Nendo 3KWP @ .5-7.75cuft @ 30hz-Alpine CDA-117-4 Cadence PA 8's -AQ 200.2-2 AQ Supertweeters-XS Power D3400-270a Mecman Alt -Knu Konceptz Wire Link to comment Share on other sites More sharing options...
mikeg321 Posted March 13, 2013 Report Share Posted March 13, 2013 I'm really not familiar with sundown subs so I don't know what kinda enclosure/power they like. I'm pretty sure Torres calculator has a box for external port so you'd just enter your port length then enter the external length. If your move the port out of the box it will lower the tuning a little but I doubt it would make an audible difference. 4 fully loaded Fi sp4 15's 2 Crescendo bc5500s Crescendo c1100.4 6 focal mids Vifa tweets 5 XS Power d3100's Pioneer avh-p4200dvd All crammed into a mustang. http://www.stevemeadedesigns.com/board/topic/150569-mikeg321s-fi-nendo-mustang-getting-walled-videos-page-4/ Link to comment Share on other sites More sharing options...
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